The present invention relates to a method of analysing for an alkyl ketene dimer.
Alkyl ketene dimers are higher analogues of diketene and are of the formula ##STR1##
where each R.sup.1 represents the same or different alkyl group (usually a long chain alkyl group, e.g. C.sub.14 -C.sub.18). Generally the alkyl group is a linear, straight chain group.
Alkyl ketene dimers (AKD) are used in the sizing of paper, for which they are preferred to rosin sizes for certain applications. For a number of applications, it may be desired to analyse for the AKD either qualitatively or quantitatively, e.g. on the sized paper or in the water drained through the wire of a Fourdrinier machine. The most common technique used for the study of AKD sizing is by radioactive tracers. Although this technique permits an accurate determination of AKD size retention in paper, it is limited to use in specialised laboratories. IR and HPLC have been tried for analysis of AKD but they are quite complex and not particularly convenient.
It is therefore an object of the present invention to provide a method of analysing for an alkyl ketene dimer which obviates or mitigates the abovementioned disadvantages.